Diaphragm pump with single compression roller



Nov. 5, 1968 J. o. DJICMILLAN 3,408,947

DIAPHRAGM PUMP WITH SINGLE COMPRESSION ROLLER Original Filed May l2, 1960 l I 4 l 5- 20 2| 26 1\\ i8 27 6 22 2\ 24 22 Z3 29 29 I L..E 1 1g 1 HIS' 22 Q L 25 L INVENTOR. JAMES o. McMlLLAN ATTORNEY United States Patent 3,408,947 DIAPHRAGM PUMP WITH SINGLE COMPRESSION ROLLER James O. McMillan, Wichita, Kans., assignor to William J. Easton, Jr., Wichita, Kans. Continuation of application Ser. No. 28,722, May 12, 1960. This application Mar. 14, 1967, Ser. No. 623,048 18 Claims. (Cl. 103-149) ABSTRACT OF THE DISCLOSURE A diaphragm pump having a substantially annular pumping chamber defined between a housing and a flexible diaphragm within and sealed to the housing, such diaphragm being disposed about the periphery of an eccentrically mounted, generally circular compression member whereby the compression member cyclically and in a circumferentially progressive manner urges the diaphragm radially outward into contact with the housing to cause circumferential movement of fluid in the pump chamber from an inlet to an outlet communicating therewith on opposite sides of a fixed position of attachment of the diaphragm to the housing.

This application is a continuation of my copending application entitled, Diaphragm Pump With Single Compression Roller, which was filed May 12, 1960, and which bears application Ser. No. 28,722, now abandoned.

This invention relates in general to pumps and particularly to a pump having a cylindrical diaphragm fixed at one point on its periphery to a pump body and acted upon by an internal compression member. This invention is related to my invention disclosed in my copending application entitled Diaphragm Pump With Double Compression Roller filed May 12, 1960 and bearing Ser. No. 28,720, now abandoned.

It is extremely desirable in pump design to eliminate all possibility of contact between the fluid being pumped and the moving parts of the pump as well as the packing and sealing elements. In this manner contamination of fluid and pump elements is eliminated and the need for packing is kept at a minimum or entirely done away with. Thus, wear is minimized; the cost of the pump is lowered; and maintenance is reduced to a very simple operation.

In our highly industrialized and complex culture of today pumps play a very important part and there is a definit advantage to have available a pump design which can be applied to many different functions. With my design, only changes in physical proportions, and in some cases, uses of special materials need be resorted to. Teardown time is reduced to a bare minimum inasmuch as elements can be removed and replaced rapidly.

The objects of my invention are:

First: to provide a pump employing a pump housing, end walls on the housing providing a cylindrical pump chamber in the housing, an eccentrically positioned diaphragm in the pump chamber attached to the pump housing at one point on the periphery of said diaphragm and forming a fluid chamber between the diaphragm and the pump body, an inlet on one side of the point of attachment of the diaphragm, and an outlet on the other side of the point of attachment of the diaphragm, the diaphragm being sealed along its peripheral edges at the point of juncture of the end walls and the pump housing, and an eccentric compression member contacting the inner peripheral surface of the diaphragm, and an eccentric roller concentric with the compression member adapted to be driven from externally of the pump to roll the compression member and diaphragm against the inner peripheral wall of the pump housing and force liquid from the fluid chamber out through the discharge outlet.

Second; to provide a diaphragm of greater width than the area in which it is installed and to install said diaphragm under pressure to deform the diaphragm in such a manner that the compression member, when acting against said diaphragm will not stretch it but will force it from one deformed position to its opposite deformed position during the pumping action.

Third; to use the diaphragm as a seal between the suc tion inlet and the discharge outlet.

Fourth; to form the inner peripheral wall of the pump housing in an arcuate cross-sectional configuration, and to form the outer peripheral edge of the compression member in an arcuate cross-sectional configuration complementary to that of the pump housing so that the di aphragm between the pump housing and the compression member will be forced into the arcuate peripheral area of the pump housing. T

Fifth; to provide a pump of the class described in which a cylindrical pump chamber is provided in a pump housing, a diaphragm is received under endwise compression in the pump chamber, the peripheral edges of the diaphragm being secured at the side peripheral edges of the pump chamber, the central peripheral portion of the diaphragm being secured at one point to the pump housing between an inlet and outlet, deforming said central peripheral portion of the diaphragm to form a fluid chamber between the inlet and outlet, and an eccentric compression member journaled in the housing and positioned in the pump chamber bearing against the central peripheral portion of the diaphragm and adapted to exert pressure on the diaphragm through a changing arc of 360 to force fluid from th fluid chamber from inlet port to outlet port.

Other objects and advantages as well asthe construction and operation of my invention in its several modifications will be apparent by reference to the following description in connection with the accompanying drawings in which: f

FIGURE 1 is a vertical cross-sectional view on the line 11 of FIGURE 2 through one form of my pump employing a diaphragm of substantially uniform configuration in cross-section, parts being shown in ielevation.

FIGUREZ is a vertical, longitudinal, *iiross-sectional view on the line 22 of FIGURE 1.

FIGURE 3 is a vertical, longitudinal, cross-sectional view through a modified form of diaphragm pump.

FIGURE 4 is a cross-sectional view through a fragmentary part of the diaphragm shown in FIGURES 1 and 2 before installation and compression. I

FIGURE 5 is a similar view through the diaphragm shown in FIGURE 3.

Referring now to the drawings using reference numbers for the various parts, l'designates a pump housing employing annular body 2 with end plates 3 and 4 which enclose a central cylindrical chamber 5. The inner annular peripheral surface 6 of the chamber 5 is substantially arcuate in cross-sectional configuration the purpose of which will be hereinafter explained.

In one form of my invention as shown in FIGURES 1, 2 and 4, the shape of the diaphragm 7 is cylindrical, the outer peripheral web 8 being substantially uniform in cross-section. The web 8 is provided with peripheral inwardly disposed flanges 9 which, when assembled, are locked in grooves 10 formed between plates 3 and 4 and the annular body 2. The diaphragm, being greater in width than the distance between the side plates 3 and 4 must be compressed when assembled and is therefore under constant compression. The angular ribs 11 projecting from end plates 3 and 4 bear against the end flanges 9 and aid outlet to the pump body 2 by means of anchoring member 14,,removablyreceived in aperture in the pump body .2, ,a nut16, removably securingsaid anchoring member.

{The opposite end-:of the anchoring member 14 carries a plate 17 which is molded into the diaphragm 7. When nut 16 is firmly drawn up the diaphragm is firmly secured to the pump body 2 at one point in the periphery ofthe diaphragm and forms .a seal between the, inlet 12 and outlet 13, with the remaining portion of the diaphragm peripheral web 8 being free to move under pressure of the compression member or contactor 18.

The compression member or contactor 18, in one form of my invention, has an arcuate outer periphery 19 and web 20. The compression member is mounted on bearing member 21 carried by eccentric bushing 22 on shaft 23, the eccentric bushing being for the purpose of adjusting the pressure of the compression member against the diaphragm, lock nut 24 being adapted to lock the bushing 22 in adjusted position on shaft 23.

Said shaft 23 is eccentrically projecting from drive shaft 25 suitably journaled in bearings 26 carried by hub 27 of end wall or plate 3. Oppositely located end wall or plate 4 may be provided with removable inspection and adjustment plate 28.

The compression member 18, in FIGURE 1, is shown at the top of its stroke. When at the bottom of its orbit the compression member will force the diaphragm into the position shown by-dotted lines in FIGURE 2.

A fluid chamber 29 is formed between the diaphragm and the pump housing annular body 2 and rotation of the drive shaft 25 causes rotation of the eccentric shaft 23 to move the center of compression member 18 through an orbit which will cause constantly changing pressure of compression member against the diaphragm to force fluids from the fluid chamber progressively'from fluid inlet to fluid outlet. There will be little or no friction or movement between compression member and the diaphragm, and consequently, no wear or noise. Ball bearing member 21 takes up all friction in the driving of the compression member.

There is no contact between the fluids being pumped and any of the moving parts of the pump and therefore no contamination of the fluids, nor wear of moving parts by abrasives in the fluids. Chemicals may be pumped without detrimental effects on moving parts. Although generally the diaphragm may be made of neoprene, it is obvious that the material from which the diaphragm is formed will depend on the characteristics of the fluid being pumped. The same is true of the pump body which may be of stainless steel or any other material consistent with the requirements of the pump, the form and operation of my invention remaining the same.

Inasmuch as pressure against fluids being pumped is constant, there are no shock loads thereby making it possible to run the pump at high speeds. No valves are needed, and sealed bearings eliminate the need for lubrication. The pump can be compactly made and capable of extremely high efficiency in operation. The pumps may be driven by direct drive from a motor or by pulleys and belts.

I have provided an alternate form of pump which is illustrated in FIGURES 3 and 5, in which the diaphragm 7' has an annular inwardly projecting rib 30. A rigid compression member or contactor 18 bears against this rib and carries central ball bearing member 21' in which eccentric bushing 22' is mounted, shaft 23' passing through the bushing and locked in relation to said bushing by nut 24. a

I The diaphragm 7' normally has the form shown in FIG- URE 5 but when compressed into position in the pump body 2, the peripheral edges 31 are securely held in grooves 32 formed in body 2 and between end plate 4' and the body. In this form of pump one end wall 3' can be formed integrally with the pump body. Inspection and access plate 28' may be provided in end plate or wall 4'.

Also, in this form of my pump, the inner peripheral face 6' is arcuate in cross-sectional configuration and the diaphragm 7' may be forced into this arcuate area by the compression member. When the diaphragm is not being forced against. surface 6 it assumes the shape shown at the bottom of FIGURE 3. This form of'diaphragm providesfor increased operating pressures over, the form shown in FIGURES g1 and;2, a smaller diameter circle of rolling point of contact being provided. The peripheral edges 31 may be reinforced "with spring steel or other resilient wire rings 33. 4.

From the foregoing it will be evident that I have provided a pump with new and novel features employinga diaphragm concentrically mounted at its peripheral edges in a pumping chamber, with its peripheral web secured at one point between an inlet and outlet to form a fluid chamber between the diaphragm and the pump body, the peripheral web being deformed to a shape eccentric to the pumping chamber, and an annular compression member concentric with the peripheral web but eccentric to the pumping chamber, rotation of said compression member causing pressure of thediaphragm against the peripheral wall of the pumping chamber through a changing arc of 360 to force fluid from the inlet end of the fluid chamber through the outlet at the other end of the fluid chamber.

It is obvious that changes in form, proportionand details of construction may be resorted to without departing from the spirit of my invention and I reserve all rights to such changes as come within the scope of these. specifications and the claims which follow. I i

What I claim as new and desire to secure, by Letters Patent is:

1. A diaphragm pump comprising an annular chamber defined jointly by a hollow pump body having a generally cylindrical internal surface with a central axis, and an annular, generally cylindrical flexible and resilient diaphragm substantially concentrically disposed within the pump body and secured adjacent its axial extremities:to the pump body, means sealingly connecting the diaphragm and the pump body throughout the axial extent of the chamber for a minor portion of the circumference of the chamber, said diaphragm in repose and apart from the pump body having a greater axial extent than when secured to the pump body, whereby said diaphragm is under axial compression and is normally flexed radially inwardly intermediate its. axial extremities throughout its circumferential extent from the pump body except adjacent said last means, inlet and outlet ports in the pump body communicating with the chamber at circumferentially spaced positions closely adjacent the opposite sides of said last means, and compression means disposed within the diaphragm and mounted for rotation about said central axis, said compression means including a single contactor disposed within the diaphragm, said contactor having a circular external periphery in a plane normal to central axis, said contactor being eccentrically, positioned with respect to said central axis by an amount sufficient to engage and position a circumferential portion of the diaphragm into sealing-contact with the internal surface of the hollow pump body throughout the axial extent of the chamber, said contactor having at least a major proportion of its entire circumferential extent engaging the diaphragm, the arrangement beingsuch that the portion of the diaphragm positioned by the contactor will progressively travel along at leasta major portion of the circumferential extent of the diaphragm during rotation of the compression means.

2. The combination of claim 1, wherein said means sealingly connecting the diaphragm and the pump body comprises means for holding a portion of the diaphragm against the internal surface of the hollow pump body,

the arrangement being such, when said portion of .the diaphragm urged into sealing contact with the internal surface of the hollow pump body by the contactor is diametrically opposed to the portion of the diaphragm held by the last recited means, that the latter portion of the diaphragm is intermediate its axial extremities spaced from the contactor.

3. The combination of claim 2, including said diaphragm having a pair of reinforcing rings imbedded therein adjacent its axial extremities.

4. The combination of claim 2, wherein the contactor is radially movable relative to the central axis whereby the eccentricity thereof is adjustable, and means for releasably securing the contactor in adjusted position.

5. The combination of claim 2, wherein the contactor is carried by a pivotally mounted eccentric whereby radial displacement of the contactor from the central axis can be adjusted by pivotal movement of the eccentric, and means for releasably securing the eccentric in selected pivotally adjusted position against pivotal movement, whereby the eccentricity of the contactor can be selectively fixed.

6. The combination of claim 2, wherein said contactor is mounted on the compression means for rotation about its center.

7. The combination of claim 2, wherein the internal surface of the hollow pump body is axially concave, and the external surface of the diaphragm is axially concave by virtue of the diaphragm being under axial compression.

8. The combination of claim 2, wherein the external configuration of the contactor is axially convex.

9. The combination of claim 2, wherein the diaphragm includes a radially inwardly. projecting rib at a position intermediate the axial extent of the chamber, with the contactor engaging the rib portion of the diaphragm.

10. The combination of claim 2, wherein said means for holding a portion of the diaphragm against the internal surface of the hollow pump body comprises an insert imbedded in the diaphragm, a radially extending stern secured to the insert, and said stem being releasably fastened to the pump body.

11. The combination of claim 2, wherein the hollow pump body is provided with an integral end wall, said end wall having an annular groove receiving an axial extremity of the diaphragm, and said compression means including a shaft journaled through said end wall.

12. The combination of claim 2, wherein said hollow pump body is provided with an axially removable end wall releasably secured thereto, said end wall including a portion entending into the hollow pump body in spaced relation thereto, said portion having an external axially tapered annular surface, and an axial marginal portion of the diaphragm received between the hollow pump body and the tapered portion of the end wall.

13. The combination of claim 12, wherein said pump body and said end wall jointly define an annular groove having a restricted entrance that opens into the hollow pump body, said diaphragm having a flange adjacent an axial extremity of said marginal portion of the diaphragm, said flange being received within said groove.

14. A diaphragm pump comprising an annular chamber defined jointly by a hollow pump body having a generally cylindrical internal surface with a central axis, and an annular, generally cylindrical diaphragm normally concentrically disposed within the pump body and secured adjacent its axial extremities to the pump body, said diaphragm intermediate its axial extremities normally being radially spaced from the internal surface of the pump body, means scaling ly connecting the diaphragm and the pump body throughout the axial extent of the chamber for a minor portion of the circumference of the chamber, inlet and outlet ports in the pump body communicating with the chamber at circumferentially spaced positions closely adjacent the opposite sides of said last means, said diaphragm including intermediate its axial extremities a radially inwardly projecting rib about substantially its entire circumferential extent, and compression means disposed within the diaphragm and mounted for rotation about said central axis, said compression means including only a single contactor disposed within the diaphragm, said contactor having a circular external periphery in a plane normal to said central axis, said contactor being eccentrically positioned with respect to said central axis by an amount suflicient to engage and position a circumferential portion of the diaphragm into sealing contact with the internal surface of the hollow pump body throughout the axial extent of the chamber, said contactor having at least a major proportion ofits entire circumferential extent engaging the rib of said diaphragm, the arrangement being such that the portion of the diaphragm positioned by the contactor will progressively travel along at least a major portion of the circumferential extent of the diaphragm during rotation of the compression means, said means sealingly connecting the diaphragm and the pump body comprising means for holding a portion of the diaphragm against the internal surface of the hollow pump body, the arrangement being such, when said portion of the diaphram urged into sealing contact with the internal surface of the hollow pump body by the contactor is diametrically opposed to the portion of the diaphragm held by the last recited means, that the latter portion of the diaphragm is intermediate its axial extremities spaced from the contactor.

15. The combination of claim 14, wherein the internal surface of the hollow pump body is axially concave, and the external surface of the diaphragm is axially concave.

16. The combination of claim 14, wherein the contactor is radially movable relative to the central axis whereby the eccentricity thereof is adjustable, and means for releasably securing the contactor in adjusted position.

17. The combination of claim 14, wherein the contactor is carried by a pivotally mounted eccentric whereby radial displacement of the center of the contactor from the central axis can be adjusted by pivotal movement of the eccentric, and means for releasably securing the eccentric in selected pivotally adjusted position against pivotal movement, whereby the eccentricity of the contactor can be selectively fixed.

18. The combination of claim 17, wherein the contactor is rotatably mounted on the eccentric.

References Cited UNITED STATES PATENTS 2,583,572 l/l952 Huber l03149 3,067,692 12/1962 Brkich 103149 FOREIGN PATENTS 717,829 10/1931 France.

874,057 4/ 1942 France.

562,409 6/1944 Great Britain.

FRED C. MATTERN, JR., Primary Examiner. W. J. GOODLIN, Assistant Examiner. 

